As it is commonly known, dye is used in many fields. In traditional industries, dye is used for ink, dope, lacquer, marker and the like, such as ink, coating ink, dope for outdoor and indoor use, and various color lacquer and the like. In recent years, with the application of computer and digital technology, the material for digital-designed color data recording has gradually replaced traditional technology and boomed rapidly. Dye is increasingly used in the inkjet ink and laser ink.
As colorant compared to paint, dye has much better water-solubility, color emissivity and color saturation, so has relatively wider applications. However, dye has many disadvantages per se, here is worse weather-resistance. For example, the light-resistance and gas-resistance thereof are worse than paint, which makes quality of the formed images susceptible to degradation. Specifically, the dye is susceptible to degradation under light, for example, UV, visible light, and is susceptible to degradation under the effect of oxidizing gases in the air such as ozone, NOx, SOx, H2S, which means it has poor light-resistance and gas-resistance. Even if not illuminated by intensive light, color change will happen by contact with air and indoor light when stored indoors for a long time, which causes poor stability.
In recent years, we have carried out much study on the weather-resistance especially the light-resistance and gas-resistance of dye, which is generally classified into two methods: develop and select novel weather-resistant dye, such dye may have special structure or have the required weather-resistance; Another method is to add functional additive to improve the light-resistance of dye. The second method is simple and easy to apply, while is only a solution to the symptoms but not getting to the root of the problems, and the adding of the additive will also cause new problem. The first method can get to the root of the weather-resistance problem, hence much work has been done with study on development of novel weather-resistant dye and much progress has been made.
The U.S. Pat. No. 5,948,154 submitted in 1996 has proposed a yellow ink composition, which adopts composition of yellow dyes with the general formulas (XI) and (XII). For yellow dyes, the known C.I. acid yellow 17 and 23 have super water-solubility but poor water-resistance. C.I. direct yellow 86, 100 and 142 have excellent light-resistance but are susceptible to jammed inkjet head. However, the yellow ink composition of the patent not only has excellent light-resistance and water-solubility, but also has storage stability, no jammed inkjet head.

The Chinese patent application applied in October, 2002 (application No. 02147082.0) has disclosed a black water-based ink composition suitable for outdoor print, which has excellent light-resistance, gas-resistance and storage stability, and can form high-quality image. The ink composition selects tri-azolo type dye as black colorant, selected from compounds of formula (I). It is a novel tri-azolo type dye, and has better storage stability when M in the formula is organic ammonium.

The U.S. Pat. No. 6,852,154B2 applied in April, 2003 has disclosed a magenta prinking ink composition, which uses the dye of following formula (I) or salt thereof as magenta colorant to improve light-resistance. The ink can be used in combination with yellow and cyan ink. The patent has also disclosed an ink composition comprising two types of magenta inks with different color density, wherein the dye of formula (I) was used in the low-density magenta ink. The ink composition can form non-particulate image. The ink preferably also comprises non-ion surfactant, preferred alkynediols surfactant and penetration promoter and preferred glycol ether.

The Chinese patent application applied in September, 2004 (application No. 200480035102.1) has proposed an ink, which uses following formula as magenta dye, the compound of formula (1) has the function of improving light-resistance fastness and gas-resistance fastness. Such compounds can be used either separately in one type or in combination of several types. Meanwhile, by adding carboxyl aryl compound and/or salt thereof into the ink, light-resistance, gas-resistance, anti jam and wet-resistance can be simultaneously obtained. Especially when using lithium salt thereof, remarkably excellent anti-jam performance can be obtained

Although these progresses in study have been made, the novel weather-resistant dye with better weather-resistance is still in demand in this industry.